(1) Field of the Invention
This invention relates generally to diphenylpyridazinone derivatives which exhibit valuable herbicidal and plant growth regulant properties. This invention also relates to novel agricultural chemical compositions and methods for controlling, inhibiting and modifying the growth of a broad spectrum of plant life.
More specifically, the class of compounds of the present invention has been found to be effective both in controlling unwanted plants as well as influencing the growth and development of valuable agricultural crops and aesthetic or ornamental plants.
(2) State of the Art
A few diphenylpyridazinone derivatives which fall within the scope of this invention have been disclosed in the literature. In U.S. Pat. No. 2,839,532, June 17, 1958, 4-cyano-5,6-diphenylpyridazinone-(3) having pharmaceutical activity is disclosed. No agricultural or similar utility is disclosed. Nannini et al., Eur. J. Med. Chem.-Chimica Therapeutica, Jan.-Feb., 1979-14, pp. 53-60 discloses analogous diphenylpyridazinone derivatives which evidence pharmaceutical activity, specifically anti-inflammatory activity. No agricultural or similar utility is disclosed. Knotz, Sci. Pharm., 41 (1973) 9-18, discloses selected N-2-substituted 5,6-diphenyl-3-oxo-4-cyano-2,3-dihydropyridazine species. The article does not disclose any agricultural or like utilities. Also, selected diphenylpyridazinones of the present invention are disclosed in application U.S. Ser. No. 11,416, filed Feb. 12, 1979, now U.S. Pat. No. 4,238,490, which compounds demonstrate pharmaceutical activity and, more particularly, are shown to be effective hypertensive agents.
U.S. Pat. Nos. 2,805,926, 3,652,562, 3,709,885, 3,870,502, 4,013,658, 4,229,205, 4,242,121 and 4,256,884 and the literature references Willemot, Plant Physiol., 60 (1977) pp. 1-4, and John et al., Plant Physiol., 57 (1976) pp. 257-59, disclose pyridazinone compounds having herbicidal and/or plant growth regulant utility.